|
Search: id:A140055
|
|
|
| A140055 |
|
E.g.f.: A(x) = G(G(x)) where G(x) = x*exp(A(x)) such that G( x*exp(-G(x)) ) = x and G(x) is the e.g.f. of A140054. |
|
+0
3
|
|
| 1, 4, 42, 764, 20400, 731862, 33397168, 1867950856, 124680486816, 9733666171850, 874978919826264, 89437471672859532, 10289414670501314608, 1320997962702267801070, 187894667581541881127640
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
EXAMPLE
|
E.g.f.: A(x) = x + 4*x^2/2! + 42*x^3/3! + 764*x^4/4! + 20400*x^5/5! +...
x*exp(A(x)) = x + 2*x^2/2! + 15*x^3/3! + 220*x^4/4! + 5025*x^5/5! +...
where G(x) = x*exp(A(x)) satisfies G(G(x)) = A(x).
|
|
PROGRAM
|
(PARI) {a(n)=local(A=x); for(i=0, n, A=x*exp(subst(A, x, A+x*O(x^n)))); n!*polcoeff(subst(A, x, A), n)}
|
|
CROSSREFS
|
Cf. A140054 (x*exp(A(x))).
Sequence in context: A137645 A136045 A074768 this_sequence A134356 A111829 A130545
Adjacent sequences: A140052 A140053 A140054 this_sequence A140056 A140057 A140058
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Paul D. Hanna (pauldhanna(AT)juno.com), May 03 2008
|
|
|
Search completed in 0.002 seconds
|
